Controller area network (CAN) bus is a message-based communications bus protocol that is often used within automobiles. The CAN bus protocol is used to enable communications between various electronic control units (ECUs), such as an engine control module (ECM), a power train control module (PCM), airbags, antilock brakes, cruise control, electric power steering, audio systems, windows, doors, mirror adjustment, battery and recharging systems for hybrid/electric cars, and many more. The data link layer of the CAN protocol is standardized as International Standards Organization (ISO) 11898-1. The standardized CAN data link layer protocol is in the process of being extended to provide higher data rates. The extended protocol, referred to as CAN Flexible Data-Rate or “CAN FD,” is moving towards standardization in the form of an update of the existing ISO 11898-1 standard.
One growing concern with in-vehicle networks, such as in-vehicle networks that use the CAN bus protocol, is network security, including intrusion detection and intrusion prevention. For example, a compromised in-vehicle network could allow an attacker to maliciously control components of a vehicle.